364 COSMOS. 



As felicitous presentiments and sports of fancy such sub- 

 sequently realized speculations as abound in Grecian anti- 

 quity sometimes contain the germ of correct views long 

 prior to any actual observation, so we find in the writings 

 of Cardinal Nicolaus de Cusa (in the second book De 

 doc fa Ignorantia), which belong to the middle of the fifteenth 

 century, the clearly expressed opinion that the body of the 

 Sun itself is only " an earth-like nucleus, surrounded by a 

 circle of light as by a delicate envelope ; that in the centre 

 (between the dark nucleus and the luminous covering ?) there 

 is a mixture of water-charged clouds and clear air, similar to 

 our atmosphere; and that the power of radiating light to 

 vivify the vegetation of our Earth, does not appertain to the 

 earthy nucleus of the Sun's body, but to the luminous covering 

 by which it is enveloped." This view of the physical condi- 

 tion of the Sun's body, which has hitherto been but little 

 regarded in the history of astronomy, presents considerable 

 similarity with the opinions maintained in the present day. 7 



world in 1842." Arago, in the Annuaire du Bureau des 

 Longitudes pour Van 1846, pp. 464, 471. Sir John Herschel, 

 in his Outlines of Astronomy, p. 234, 3*95 (edition of 

 1849), thus expresses himself: " Above the luminous surface 

 of the Sun, and the region in which the spots reside, there 

 are strong indications of the existence of a gaseous atmo- 

 sphere, having a somewhat imperfect transparency." 



* I would, in the first place, give in the original the pas- 

 sages to which I refer in the text, and to which my attention 

 was directed by a learned work of Clemens. (Giordano Bruno 

 und Nicolaus von Cusa, 1JJ47, 101.) Cardinal Nicolaus de 

 Cusa (whose family name was Khrypffs, i. e. Crab), was born at 

 Cues, on the Moselle. He thus writes in the twelfth chapter 

 of the second book ot the Treatise De docta Ignorantia 

 (Nicolai de Cusa Opera, ed Basil, 1565, p. 39), a work that 

 was much esteemed at that age : " Neque color nigredinis est 

 argumentum vilitatis Teme; nam in Sole si quis esset, non 



